JetBoil is a brand not a product, at least not any longer...
There are 8 different versions available going from 0.8L to 5 L (0.85 to 5.28 quartz0
The basic idea is the same, an integrated burner/pot combination with FluxRing to capture some of the heat that is normaly lost up to the sides , but of course the 8.5 oz Ti .8 pot system is not going to work like the 48oz group version...
http://www.jetboil.com/products/comparesystems
BTW, I have the original 1 L version.
The piezo does not work (in fact I removed it long ago) but apart from that it works very well.
I prefer to use the Caldera Cone for what I do but still occasionally use the Jetboil if I want something quick and easy for two people or for a hot cuppa when car camping.